Yarrow

Achillea millefolium

flower

A flat-topped native perennial producing broad clusters of tiny white, yellow, or pink flowers beloved by a remarkable diversity of beneficial insects. Called the landing pad of the insect world, yarrow flowers attract predatory wasps, hoverflies, lacewings, and parasitic wasps that hunt aphids, caterpillars, and other pest insects. Extremely tough, drought-tolerant, and long-lived.

✅ Plant alongside

Good neighbors that attract beneficial insects or deter pests

• Most vegetables — One of the single most effective beneficial insect attractants available; parasitic wasps that visit yarrow flowers also control aphids and caterpillars throughout nearby beds
• Tomato — Hoverflies and parasitic wasps visiting yarrow significantly reduce tomato hornworm and aphid pressure
• Brassicas — Tiny wasps and hoverflies that feed on yarrow nectar also parasitize cabbage worms and aphids
• Any vegetable — Plant along borders for a season-long stream of aphid predators and crop pest parasitoids

🛡️ Pest & disease prevention

Proactive ways to stop trouble before it starts — tap a name with an arrow for its full guide

• Powdery mildew →

  Plant in full sun with good airflow; division every few years reduces mildew susceptibility

• Aphids →

  Rarely a serious problem; the insects yarrow attracts naturally keep aphids in check

• Botrytis gray mold →

  Avoid dense, damp plantings; good drainage essential

• Stem rot →

  Never plant in wet spots; raised beds or slopes preferred

🌸 Blooms & cutting

Cut stems for fresh arrangements when flowers are fully open. Yarrow holds color remarkably well when dried — hang upside down in bundles immediately after cutting for dried wreaths and bouquets. Fresh yarrow has a slightly bitter, resinous scent that becomes more pleasant when dried. Common white yarrow self-seeds vigorously; deadhead if this is undesirable.

🥗 Nutrition & benefits

As a companion plant: considered one of the most powerful beneficial insect habitat plants available. Research from University of California and Cornell demonstrates that yarrow-planted borders can reduce aphid populations in adjacent crops by 30 to 60 percent due to increased parasitoid wasp activity.

⚠️ Toxicity & safety

Yarrow is mildly toxic to dogs, cats, and horses if eaten, and handling the ferny foliage can cause contact dermatitis - an itchy skin rash - in sensitive people. It is a traditional medicinal herb but is best grown as an ornamental and beneficial-insect plant; wear gloves if your skin is sensitive and keep pets from grazing on it.